pas steering rack

[bainsgs]

Does anybody know if the pas steering rack off a 04 model would fit a 96 model

thanks


Gurinder

[Kaz-kzukNA1]

Hi, Gurinder.

Could you kindly clarify the wording 'rack' ? Although I believe you are referring to the metal shaft inside the power steering gearbox (EPS Gbox), it is possible but not so common to disassemble it. Are you referring to the entire EPS Gbox by any chance?

Regards,
Kaz

[Hagasan]

Hi, Gurinder.

Could you kindly clarify the wording 'rack' ? Although I believe you are referring to the metal shaft inside the power steering gearbox (EPS Gbox), it is possible but not so common to disassemble it. Are you referring to the entire EPS Gbox by any chance?

Regards,
Kaz

Hi Kaz,

normal "wording" in the UK would refer the whole steering assembly as the steering "rack" ie the part with the track rods complete.

My reason for chiming in is that I'm also interested in the answer for a similar situation.

Regards,

Gary

[Kaz-kzukNA1]

Hi, Gary. Thank you for the clarification and to be clear, I will be writing the following information referring to the entire EPS Gbox assembly.

First, the background information.
EPS on NSX has been upgraded a few times. Some of the major changes are as follows;
In 1995 (NA1-130~), the EPS Power unit was integrated into the EPS Control unit.
In 1997 (NA1-140~, NA2-100~), the rotation sensor was removed from the EPS Gbox assy and thus, the control software was also modified.
In 1999 (NA1-150~, NA2-110~), further control software modification was applied.

So, as you can see, the EPS Control unit on 96 model requires the input from rotation sensor that is not available on 04 model. There are two connectors on the EPS Gbox assy upto/including the 96 model and just one from 97 model onwards. The diagram on the parts list shows 2 connectors regardless of the model year so be careful.

If you can get hold of 04 EPS Gbox assy, then it's worth getting the latest EPS control unit as it'll provide you the most smooth feeling over the wide speed range.
The original EPS showed big change in power assist before/after around 40kph and then it was improved in 1997 with the changes stated above. Further improvement on the 'assist feeling' was applied later.

So, you will need to investigate the wiring compatibility but I know this modification is possible as some of the early model owners replaced the system with the latest EPS control unit and Gbox assy. Also, there were some people who replaced with just the latest EPS control unit and kept the earlier EPS Gbox assy. My car was delivered without the EPS so I wanted to do the latest EPS Gbox and control unit combination but I couldn't afford it as the EPS Gbox assy is so expensive...

Hope this will help you a little.

Regards,
Kaz

[nigel]

Kaz, are you saying you can get a later edition EPS control box and simply replace it in the early,(92) model year cars and get a better feel without actually changing the entire steering rack assy.?

Cheers
nigel

[Kaz-kzukNA1]

Hi, Nigel.
The simple answer for your question is No, I'm afraid.

Instead of focusing on the '92 car, I am going to talk about the EPS gbox from '92 car.

In order to utilise the EPS gbox from ‘92 model with the latest EPS control unit, you will need to sort out the following points. There are several conditions to be considered so I hope I won’t get confused….

In summary, it’s not a plug and play modification.

Let’s start with the basic.

When NSX was introduced on the market, the EPS was originally available only for the AT model.
From ‘93, EPS was available as an option even for the MT model except for the Type-R.
Until ‘95, the EPS Power box was placed under the passenger floor and the Control unit was placed behind the glove box.
From ‘95, the EPS Power and Control unit were integrated into a single box.
From ‘97, the rotation sensor was removed from the EPS gbox assy.
The universal joint at the steering column is different between EPS and non-EPS car.
For MT, you’ll need the pulse sender unit (behind your seat) to send speed information to the EPS Control unit. For AT, this information will be passed through the AT Control unit.
It’s a small thing but if you source the parts from outside US, please be careful as some of the parts such as bracket to hold the control unit are different between RH and LH drive model.

So, as you can see, if you want to fit the latest EPS Control unit to the AT model prior to '95 using the EPS gbox from ‘92, then you need to source a special loom as the EPS Power and Control unit were integrated into one box in the latest spec. You may also need to make small modification depending on the year model for the connection between the AT and EPS Control unit. Honda doesn’t source a loom just for the EPS so if you want to use OEM part only, you’ll need to replace the entire front loom which will be very costly. I’m not familiar with the aftermarket parts in US so not sure whether you can source this kind of loom or not there. I only dealt with the NSX parts from Japan.

If you want to fit the latest EPS Control unit to the MT model prior to '95 using the EPS gbox from ‘92, then you need to source a special loom because of the above reason plus the Pulse sender unit and the additional loom to connect it to the EPS Control unit. Also, the universal joint at the steering column is different if the car was delivered without EPS originally so you must replace it with the correct type.

Hope this will provide you with some idea….

Regards,
Kaz

[michaelw]

To be honest i wouldn't proclaim to know much about the subject but have been bitten by this before. My '95 car had a problem with the inner ball joint and to cut a long story short I then needed a new rack. However the only 2nd hand one was, I believe, off a later car so the pinion assembly was taken off the old rack and put on the new because of the sensor.

However when the rack was put back on the car the steering was very light one way and too heavy the other which felt to me like the PAS was trying to self centre to one lock rather than the middle.

I ended up with a new rack which is something approaching £7000 I think. As I say I am not sure of the details as you can tell from the above but would be very wary of swapping bits from one rack to another. It may have been something simple but a lot of research was done at the time and no solution could be found.


Michael.